There are some disease states where a patient needs to constantly administer a medicament to keep the disease in check. Typically the medicament is delivered by injection, infusion or inhalation one or more times a day. There is always the risk that a patient will accidentally overdose the medicament or suffer some physiologic incident that requires the administration of a second medicament to correct the problem. For example, people suffering from diabetes typically inject themselves with insulin to control their blood sugar. Insulin is a hormone that reduces blood sugar and is normally produced by the pancreas in response to increased glucose levels in the blood.
Hypoglycemia is a condition that is relatively common in persons with diabetes and occurs when the blood sugar (glucose) is too low, typically below 70 mg/dL. Hypoglycemia occurs when the blood sugar (glucose) is used up too quickly, or glucose is released into the bloodstream too slowly, or too much insulin is released into the bloodstream. Another hormone, glucagon, can be used to counteract hypoglycemia by producing the opposite effects to those of insulin, including, primarily, increasing hepatic glucose output and thereby increasing blood glucose levels. Glucagon levels tend to increase when blood glucose levels fall to abnormally low levels, particularly in patients who utilize insulin injections.
Current goals for diabetes management include near normal blood glucose levels to delay or prevent microvascular complications; achievement of this goal usually requires intensive insulin therapy. In striving to achieve this goal, physicians have encountered a substantial increase in the frequency and severity of hypoglycemia in their diabetic patients. Frequent recurrent bouts of hypoglycemia can be associated with hypoglycemic unawareness that can further contribute to development of hypoglycemia, which is sometimes severe. Thus, efforts to achieve normal glucose levels with insulin can result in the development of hypoglycemia of varying frequency and severity in patients. Hypoglycemia and the lack of awareness of its presence are serious complications of insulin therapy that occur with greater frequency and severity when impaired counter-regulatory (anti-insulin) responses are present in diabetic patients.
One of the major counter-regulatory hormones that normally responds to hypoglycemia is glucagon. An injectable form of glucagon is available as a prescription emergency kit, for use to treat severe insulin reactions. The glucagon is injected and raises blood glucose levels within a half-hour. It is frequently recommended that people with Type 1 diabetes, and other people taking insulin injections, have a family member learn how to administer glucagon. Within the emergency glucagon kit are a syringe pre-filled with a liquid and a separate vial of powdered glucagon. The instructions for the kit require that the glucagon must be prepared for injection immediately before use by following a very specific reconstitution procedure to solubilize the powdered glucagon so it can be injected.
Unfortunately, these known glucagon emergency kits require a manually dexterous “operator” or “user” who is composed, confident and competent in the whole procedure. Since an insulin user usually needs administration of glucagon during seizures and/or unconsciousness they obviously must rely on others to assist them in such emergencies. However, despite public relations to increase the awareness of the life saving capability of glucagon rescue, it is still largely unknown by the general public. Indeed, studies have shown that parents of diabetic children had significant problems with glucagon emergency kits, including handling difficulties ranging from opening the container to drawing the correct dose into the syringe. Clearly, there is a need in the art to have a simplified or “fool proof” system and method for administrating glucagon by both the diabetic and in extreme hypoglycemic reactions by another person, preferably in a single injection or delivery step that is simple for the user to perform.
Our invention overcomes the above-mentioned problems by providing a single injection device that is used to inject multiple doses of a first medicament, such as insulin to treat diabetes, but also contains one or more preset doses of second medicament, such as glucagon, that can be administered to treat or prevent an adverse event, such as a hyperglycemic event. Preferably, our device would include electronics, microprocessors that would provide the user with visual and/or audio prompts to assist the user in administering the second medicament. Additionally, the injection device would have an automatic lockout feature to prevent the device from further administration of the first medicament.
These and other advantages will become evident from the following more detailed description of the invention.